Kevin Ellis scored on a header off Krisztian Nemeth's chipped cross in the 52nd minute Sunday as Sporting Kansas City downed Vancouver 1-0.
The Whitecaps could have taken sole possession of top spot in the Western Conference with a single point, but instead lost at home in Major League Soccer for the fourth time in nine games after failing to find the range while carrying the run of play in the first half.
"It hurts," said Vancouver head coach Carl Robinson. "You create a number of chances and you don't score. Sometimes it comes back to bite you in the bum and it did today."
The Whitecaps (10-8-2) were playing in front of their fans for the first time since the end of May after a five-game road trip that saw them pick up nine of a possible 15 points while B.C. Place Stadium was occupied by the Women's World Cup.
Sunday also marked the beginning of a busy summer stretch of 11 matches over the next seven weeks for Vancouver as the club competes in MLS, the Amway Canadian Championship final and the CONCACAF Champions League group stage.
Kansas City (8-3-6) improved to 6-1-3 over its last 10 matches in MLS and is now just two points back of the Whitecaps with three games in hand. The top six teams in the ultra-tight West are all within two points of each other, which made the loss even harder to swallow for Vancouver.
"It's going to be nip and tuck between now and the end of the year," said Robinson. "We know where we are. We need to be better, I need to be better. We will be better ... a lot of things need to be better."
After setting up Ellis' goal, Nemeth fired a shot off the post behind Ousted in the 58th minute that stayed out before Jacob Peterson sent the rebound just wide.
Vancouver came close to tying it in the 61st when Cristian Techera blasted an effort that Kansas City goalkeeper Tim Melia blocked with his body. The ball rebounded off Sporting defender Matt Besler and was headed towards goal, but Amadou Dia cleared the ball from danger.
The Whitecaps pressed for the equalizer late, with Tim Parker's header going just wide in the 90th minute, but couldn't find a way through on the way to suffering their second straight loss.
"We had control of this game," said Ousted. "We need that killer instinct. We need to be better at putting those chances away."
The latter stages of the match ended with Vancouver defender Kendall Waston and Kansas City forward Dom Dwyer coming together on a few occasions. Each player finished with a yellow card.
"Both good players. Both super professionals," said Robinson. "I don't think it was handled correctly."
Teams often get off to sluggish starts following long road trips, but the Whitecaps dominated the first half and could have easily found themselves ahead.
Melia made a nice stop on Kekuta Manneh in the 11th minute before Parker's glancing header from a corner was cleared off the line by Benny Feilhaber in the 13th.
Manneh then sent Techera in on a partial break three minutes later, but Dia recovered in time to make a clean tackle with the pint-sized winger bearing down on Melia to keep the game scoreless.
"Credit to them. They weathered the storm, especially in the first 45 minutes," said Robinson. "It's a tough one to swallow today."
Notes: The Whitecaps were without captain Pedro Morales and defender Pa-Modou Kah because of calf injuries. Morales sat out his fourth straight game, while Kah limped off in last weekend's 2-1 road loss to the Colorado Rapids. ... Vancouver visits the Portland Timbers next weekend.
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